[llvm] [NVPTX] Fix for LTO dwarf emission when multiple CUs with a mix of DebugDirectivesOnly and NoDebug (PR #190371)

[Alexander Yermolovich via llvm-commits]

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@@ -2123,6 +2123,7 @@ class DICompileUnit : public DIScope {
   DebugEmissionKind getEmissionKind() const {
     return (DebugEmissionKind)EmissionKind;
   }
+  bool isNoDebug() const { return EmissionKind == NoDebug; }
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ayermolo wrote:

Please add description of this API.

https://github.com/llvm/llvm-project/pull/190371